The invention proceeds from a system for actuating the brake systems of at least one wheel of a vehicle, which system detects at least one variable representing movement of a wheel, generates an instability value based on detected variables, and changes the brake pressure as a function of the instability value.
Brake systems of this type include antilock control systems, which exist in many different forms. For example, reference can be made here to the document Bosch Technische Berichte, Vol. 7, No. 2, 1980. In antilock control systems of this type, the brake systems of the wheels of the vehicle are actuated in such a way that a change in the brake pressure occurs as a function of an instability value. This instability value is generated as a function of the detected motion of the wheel, usually its rotational velocity. In particular, this instability value is a combination of the instantaneous deceleration or acceleration of the periphery of the wheel and the brake slip.
Systems for controlling the dynamics of vehicle motion are also known, in which a variable which modifies and/or represents the dynamics of the vehicle's motion such as, for example, the angular yaw acceleration, the steering angle, and/or the transverse acceleration of the vehicle, is detected. As a function of these measured variables, the brake systems of the wheels are actuated so as to increase the driving stability. A system such as this is known from, for example, the article "VDC, The Vehicle Dynamics Control System of Bosch", Advancements in ABS/TCS and Brake Technology (1995).
DE 44 46 592.0 discloses a modularly designed driving dynamics control system in which an overriding vehicle dynamics controller intervenes in a subordinate antilock control system to increase the driving stability. DE 44 46 592 corresponds to U.S. application Ser. No. 08/576,962 filed Jan. 22, 1995 and incorporated herein by reference.
The object of the present invention is to modify a known antilock controller for the purpose of increasing the driving stability.